On-line integrated cardiological database storage on magneto-optical disk autochanger

A large integrated cardiological database is operative in the authors´ Department to collect and store clinical information of more than 50,000 patients. Character-based data are entered from 21 workstations of the network. EKG tracings are entered by RS232 connection and by image scanner. Mass storage of about 600 Mbyte per year is required. To maintain at least 10 years of an on-line documentation, a 10 Gbyte magneto-optical disk autochanger was added to the network one year ago. An original software manager (JBMan) was implemented to regulate data transfer, transparently to the end user. The new information produced daily is transferred at night-time by JBMan to optical disk. All available information for the patients booked for the next day is then restored. This allows at least 95% on-line routine work through direct access to the server hard disk. Unforeseen queries can cause an optical disk change to take place into the autochanger with 15 second delay for the operator. At present, more than 109,000 files are stored on optical disks. The system seems suitable for daily operation of a large cardiological database shared on-line on the network